High mix, low volume, no problem. Change over times go way down with this handy tool changer. Simply mount the robot portion to the end of your robot. Mount the tool side to each of your tools, you will want to purchase the tool side adapter for all of your tools in scope. Then you can switch from smart grippers to pneumatic grippers, with out the need for hand tools.
The Applied Robotics manual tool changer makes changing tools easy.
If you need to switch from from a 2 finger soft gripper (use this link to access the documents) like this 
to a 4 jaws gripper like this 
, no problem. The Epsilon manual tool changer will make the process simple and efficient.
Use this link to register and access the datasheets and models.
Below is a youtube video that demonstrates how the tool changer works.